I found myself without any brake fluid the other day. I was wondering why the warning light didn't come on. As far as I can tell, it's not connected.

 

There are three empty plugs coming off the wiring loom and I'm wondering if one of these should be connected. Ones got one wire, one two and the other three wires.

 

Any help would be appreciated.

 

thanks

Peter

Edited February 1, 201511 yr by peterd

I had a look in the Gregory's KE55 Manual. The electrical wiring diagram shows a white/black to earth and a green/white to the warning lamp. The green/white actually changes to red/white at the bulb check relay.

 

The thing you have arrowed is the switch

Below applies to 30 series

 

The 1976 EWD shows the same as what I said above.

 

The 1978 EWD shows a red/white wire instead, but apparently this was only for England.

 

So essentially there will be an earth plus a wire out to the warning light.

Thanks for having a look at that for me. Do you know what the switch does?

Do you have any idea where the warning light wires attach? Apart from the switch, I can't see anything else on the mc. My gregories covers the early models but my ke35 is more ke55 i think. (1978 model) Thanks for your help.

Sorry, that's as much as I can tell you. I'm just looking at the factory wiring diagrams, and the later KE55 Gregories. It will be some sort of basic switch that completes the circuit to earth when the fluid drops below a particular level. Clearly it isn't a pressure switch. You simply need to use a multimeter from the wire at the dash warning light (which should be red/white) and test the various wires in the vicinity of the master cylinder (which should be green/white or red/white) for continuity till you find the right one.

Its called a pressure differential switch, so it's not for low fluid level its for fluid pressure loss / difference between the front & rear brakes, the master cylinder piston ( or possibly in this case the proportioning piston ) will travel further down the bore if a pressure difference is present & it will trigger the switch to come on via a plunger type needle which hangs out the bottom of the switch & it will tell the driver by bringing on the light on the dash ..

Edited February 2, 201511 yr by lexsmaz

thank you

 

that makes sense. so I assume some wires should be attached here?

One chamber was full and was empty but there was no warning light. The warning light actually glows very dimly all the time, which I assumed was an earth problem.

No wires = no warning, if the Brake warning light glows dimly all the time as you said it sounds like there is a earth issue as in wires pinched or such ..